System for automatically landing aircraft using image signals and method of controlling the same

Abstract

Disclosed herein are a system for automatically landing an aircraft using image signals and a method of controlling the system. The system includes an altimeter installed on the aircraft; a landing mark placed at a landing location on a landing runway; a camera installed on the aircraft, oriented toward the front of the aircraft, and configured to detect the shape of the landing mark in image information form; and a FCC configured to calculate the angle between the aircraft and the ground, the ground range and the slant range between the aircraft and the landing location using the altitude information measured by the altimeter, the image information of the landing mark captured by the camera, angle information composed of the pitch, roll and yaw angles of the aircraft, and the angle of entry into the landing runway, and configured to control the automatic landing of the aircraft.

1. A system for automatically landing an aircraft using image signals, comprising:
 an altimeter installed on the aircraft, and configured to measure an altitude of the aircraft; 
 a landing mark placed at a landing location on a landing runway; 
 a camera installed on the aircraft, oriented toward a front of the aircraft, and configured to detect a shape of the landing mark in a form of image information; and 
 a FCC(Flight Control Computer) configured to calculate an angle θ between the aircraft and the ground, a ground range GR between the aircraft and the landing location and a slant range SR between the aircraft and the landing location using the altitude information measured by the altimeter, the image information of the landing mark detected by the camera, and angle information composed of pitch, roll and yaw angles of the aircraft, and configured to control automatic landing of the aircraft, wherein: 
 the FCC is further configured to calculate the angle θ between the aircraft and the ground using Equation 1, 
 the FCC is further configured to calculate the ground range GR between the aircraft and the landing location using Equation 2, and 
 the FCC is further configured to calculate the slant range SR between the aircraft and the landing location using Equations 3 or 4:
   θ=tan −1 ( y ″ cos(δ)cos(α)/( x ′ cos(β)))  (1)
 
     GR=h*x′  cos(β)/( y″  cos(δ)cos(α))  (2)
 
     SR=h /sin(tan −1 ( y ″ cos(δ)cos(α)/( x′  cos(β))))  (3)
 
     SR=GR /cos(tan −1 ( y″  cos(δ)cos(α)/( x′  cos(β))))  (4)
 
 
 where α: the pitch angle, 
 β: the roll angle, 
 δ: the yaw angle, 
 x: a horizontal length of the landing mark measured from the image information detected by the camera,
     x′=x /cos(β),
 
 
 y: a vertical length of the landing mark measured from the image information detected by the camera,
     y′=y /cos(α),
 
     y″=y′ /cos(δ), and
 
 
 h: the altitude information measured by the altimeter, 
 further wherein the FCC is further configured to calculate a ground range d 1  to a nearest point that makes an angle of entry into the landing runway ψ zero at a current location using Equation 5:
     d 1=( GR−D/ 2)*sin(ψ)  (5)
 
 
 where ψ: a current angle of entry into the landing runway, and 
 D: an actual diameter of the circle of the landing mark. 
 
     
     
       2. The system as set forth in  claim 1 , wherein the image information comprises horizontal and vertical lengths of the landing mark detected by the camera, and at least one of the angle θ between the aircraft and the ground, the ground range GR between the aircraft and the landing location and the slant range SR between the aircraft and the landing location is calculated based in part upon the horizontal and vertical lengths of the landing mark. 
     
     
       3. The system as set forth in  claim 1 , wherein the altimeter comprises a radio wave altimeter. 
     
     
       4. The system as set forth in  claim 2 , wherein the landing mark is painted with luminous paint. 
     
     
       5. The system as set forth in  claim 1 , wherein the camera comprises an infrared camera.